1. Field of the Invention
The present invention relates to a substrate transferring apparatus for transferring plate-shaped substrates.
2. Description of the Related Art
Recent developments in information technology have resulted in a wide use of information display devices, and continuously increased necessity thereof. Various information display devices are known in the art ranging from conventional CRT monitors to flat panel displays such as liquid crystal displays (LCD), plasma display panels (PDP), organic light emitting devices (OLED) and the like. In particular, the LCD has been increased in importance of application in view of its utility. Specifically, due to advantages such as miniaturization, light weight, low power consumption, the LCD has been increased in its application as a replacement which can overcome disadvantages of the conventional display device such as CRT monitors.
During a process for manufacturing such a flat display device, a thin glass substrate having a thickness of about 0.7 □ is treated. Specifically, while transferring a thin and wide glass substrate to respective processing stages, various processes are performed. Meanwhile, since the flat display device requires a significantly high precision, even a minute scar can have a detrimental influence on the quality of the flat display device. Thus, when manufacturing the flat display device, it is very important in view of quality management of the products to prevent damage from being formed on the surface thereof during transfer of the substrate as well as during other processes during manufacture of the flat display device.
In this regard, as for a substrate transferring apparatus used for the process of manufacturing the flat display device, a substrate transferring apparatus which is not brought into direct contact with a surface of a substrate in order to prevent damage of the substrate have been mainly developed. In particular, a substrate transferring apparatus designed to transfer the substrate in a floated state with air is mainly used in the art. More specifically, the substrate transferring apparatus operates in such a way that rollers of the apparatus are brought into contact with very narrow portions at both sides of the substrate, and rotate to transfer the substrate while air injection nozzles inject air perpendicular to a substantial area of the substrate including a central region thereof in order to float the substrate, thereby allowing a wide substrate to be stably transferred.
However, since such an air-floating type substrate transferring apparatus requires a pump to supply a highly compressed air for the flotation of the substrate, and a pipe to connect the pump with a body of the substrate transferring apparatus, the substrate transferring apparatus has a complicated structure, causing an increase in manufacturing costs. In particular, as the surface area of the flat display device has recently been increased, the requirement for a large capacity pump has been also increased together with difficulty in the management of the pipe.
In addition, a substrate transferring apparatus which can be commonly used for transfer of substrates having various sizes via an appropriate adjustment of the apparatus according to the sizes of the substrates is urgently needed in the art.